Background: Impact of socio-demographic characteristics on prevalence of mental disorders in children andadolescents. Objectives and methods: Based on epidemiological studies published between 1987 and 2004, this reviewanalyzes associations between the prevalence of mental disorders in children and adolescents and socio-demographic characteristics.Results: The mean period prevalence without considering global psychosocial functioning amounts to 22%; thisdeclines to 16 % when deficits in global psychosocial functioning are taken into account. Prevalence rates are higher in malesthan in females during childhood, and in some studies also in adolescence. Prevalence rates in female adolescents, are higherthan in male adolescents. In young adulthood, prevalence rates tend to become more similar again. Some studies tend to showa higher probability of mental disorders in subjects of lower socioeconomic status. Conclusions: Besides the assessment ofprevalence rates and their associations with risk factors, future research should focus more on more homogenous standards ofassessment.